Recently I have a simulation program that needs to solve a large number
of linear regression A x = b, where A is symmetric and constantly
chnages. I found that the solve function is considerably less efficient
than

solve_symmetric = function(A, B)
{
chol2inv(chol(A)) %*% B;
}

So I would request that the solve function be enhanced with an
symmetric option, which defaults to FALSE, the current solve. But when
symmetric=TRUE, a more efficient algorithm for symmetric matrix is
used. Thanks.